Electrode, battery and battery pack

Abstract

According to one embodiment, provide is an electrode including an active material-containing substance, an electro-conductive agent, and a binder. The active material-containing substance contains an active material including a lithium nickel cobalt manganese-containing oxide. A ratio IAVE/ITOP of an average value IAVE of a peak intensity at ±20° C. from a peak top of a highest intensity peak in a m/z=132 curve according to evolved gas analysis-mass spectrometry to a peak top intensity ITOP of the peak top is 0.2 or more and less than 0.5. A ratio A44/A132 of an area A44 under a m/z=44 curve within a range of 550° C. to 600° C. according to evolved gas analysis-mass spectrometry to an area A132 under the m/z=132 curve within a range of 200° C. to 550° C. is 5 or more and less than 10.

What is claimed is: 
     
         1 . An electrode comprising:
 an active material-containing substance containing an active material comprising a lithium nickel cobalt manganese-containing oxide; an electro-conductive agent;   and a binder,   a ratio I AVE /I TOP  Of an average value I AVE  of a peak intensity at +20° C. from a peak top of a highest intensity peak in a m/z=132 curve according to evolved gas analysis-mass spectrometry to a peak top intensity I TOP  of the peak top being 0.2 or more and less than 0.5, and   a ratio A 44 /A 132  of an area A 44  under a m/z=44 curve within a range of 550° C. to 600° C. according to evolved gas analysis-mass spectrometry to an area A 132  under the m/z=132 curve within a range of 200° C. to 550° C. being 5 or more and less than 10.   
     
     
         2 . The electrode according to  claim 1 ,
 wherein the active material-containing substance comprises 0.4 mass % or more and 1 mass % or less of an alkali component comprising at least one of lithium carbonate and lithium hydroxide.   
     
     
         3 . The electrode according to  claim 1 , wherein the lithium nickel cobalt manganese-containing oxide is represented by Li a Ni (1-b-c-d) Co b Mn c M d O 2 , where 1≤a≤1.2, 0<b≤0.4, 0<c≤0.4, 0≤d≤0.1, and M is one or more elements selected from the group consisting of Fe, Cu, Ti, Mg, Al, W, Y, B, Mo, Nb, Zn, Sn, Zr, Ga, and V. 
     
     
         4 . The electrode according to  claim 1 , wherein the binder comprises one or more selected from the group consisting of polyvinylidene fluoride and derivatives thereof. 
     
     
         5 . The electrode according to  claim 1 , wherein the active material has a breaking strength of 30 MPa or more and 300 MPa or less. 
     
     
         6 . The electrode according to  claim 1 , wherein the active material has a particle shape, and an average particle size of the active material according to a laser diffraction scattering method is 2 μm or more and 8 μm or less. 
     
     
         7 . The electrode according to  claim 1 , wherein the active material has a particle shape, and a ratio D 90 /D 10  in a volume-based cumulative frequency distribution of particle sizes based on a particle size distribution according to a laser diffraction scattering method of 4 or less, where D 10  is a particle size at which a cumulative frequency from a smaller particle size side of the cumulative frequency distribution is 10%, and D 90  is a particle size at which the cumulative frequency from the smaller particle size side of the cumulative frequency distribution is 90%. 
     
     
         8 . The electrode according to  claim 1 , wherein the active material has a single-particle shape. 
     
     
         9 . The electrode according to  claim 1 , wherein the electrode has a density of 3.1 g/cm 3  or more and 3.5 g/cm 3  or less. 
     
     
         10 . A battery comprising:
 a positive electrode comprising the electrode according to  claim 1 ; and   a negative electrode.   
     
     
         11 . The battery according to  claim 10 , wherein the negative electrode comprises a titanium-containing oxide. 
     
     
         12 . The battery according to  claim 11 , wherein the titanium-containing oxide comprises at least one selected from the group consisting of a lithium-titanium oxide having a spinel crystal structure, a lithium-titanium oxide having a ramsdellite crystal structure, a niobium-titanium oxide, and titanium dioxide. 
     
     
         13 . The battery according to  claim 10 , further comprising a nonaqueous electrolyte. 
     
     
         14 . A battery pack comprising the battery according to  claim 10 .